Piston.



E. T.- ADAMS.

PISTON. APPLICATION FILED 00T.18, 1909.

Patented June 7, 1910.

INVEN-:H- M ATITRNEY.

WITNEEEEE za/6MM 'UNITED STATES IATENT OFFICE.

EDVVAR-D T. ADAMS, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO ALLIS- GHALMERS COMPANY, OF MILW'AUKEE, WISCONSIN, A CORIORATION GF NEV JERSEY.

PISTON.

Application led october 18, 1909.

Specification of Letters Patent.

Patented June 7, 1910.

Serial No. 523,334.

'o all whom t may concer/b:

Be it known that I, EDWARD T. ADAMS, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of fisconsin, have invented a certain new and useful Improvement in Pistons, of which the following is a specification.

This invention relates to improvements in the construction of pistons for steam or other fiuid pressure engines.A

The object of the invention is to provide a piston which will be simple and durable in its construction and efficient in operation. In pistons of large diameters it is customary to form the interior hollow and also to annularly build up the body of several independent pieces. It is to this type of piston that the invention has particular relation.

A clear conception of the invention can be obtained by reference to the accompanying drawings in which like reference characters designate the same or similar parts in different views.

Figure 1 is a central vertical section of a piston built according to the invention, showing also a fragment of the piston rod. Fig. 2 is a plan view of the device shown in Fig. 1, a portion thereof showing a section taken along the line I-I of Fig. 1. Fig. 3 is an enlarged fragmentary central vertical section of the piston shown in Fig. 1. Fig. 4 is a fragmentary plan of the device shown in Fig. 3. Fig. 5 is a view similar to that of Fig. 3 but on an enlarged scale, showing a modification applicable to a narrower type of piston. Fig. 6 is a plan of same.

The piston body 3, see Fig. 1, is fastened to the rod 1 by means of the nut 2 which clamps the body 3 against a fiXed collar 5 upon the rod 1. rIhe dowel 4 which coacts in a slot in the body 3 and in a corresponding hole in the rod 1, prevents rotation of the body 3 relative to the rod 1.

The body 3 consists of two parallel concentric disks which are tied together by the radial ribs 6. The pockets formed between consecutive ribs 6 and the disks have openings 13 near the periphery of the body 3. In the preferred form of construction, see Figs. 1, 2, 3, 4, the openings 13 are covered by a ring 9, the outside diameter of which corresponds to the outside diameter of the body 3, and the distance between the planes of the faces of the ring which are in clamping contact with the piston is equal to the distance between the plane surfaces of the piston with which the ring coacts.

In the modification, see Figs. 5, 6, the ring 9 coacts against the second ring 20, which in this case forms a covering for the openings 13. This ring 20 is of a thickness equal to the distance between the plane surfaces of the piston, with which surfaces the rings 9, 2O coact. One of the plane surfaces of the second ring 20, which surfaces are in contact with either ring 9 or piston 3, may be cut away a slight amount so as to leave a remaining surface of contact lying entirely without the circle of bolts. A packing ring 8 is located between the ring 9 and the peripheral rib 7 forming a part of the body 3 in the preferred forni, and between the ring 9 and the second ring Q0 in the modication.

The long studs 10, one end of which is screwed into the body 3, have their other ends flush with the outer face of the body 3 on the ring side thereof. The ring 9 has a series of circular pockets 14 formed therein concentric with the holes which allow the passage of the studs 10 through the ring. The studs 10 do not coact with the rings 9, 20, the holes permitting their passage there through being of greater bore than the diameter of the studs 10. These pockets 14 are of a depth equal to the height of the nuts 11. Radial slots 12 are formed in the ring 9 and body 3, which are'directcd toward the centers of the pockets 14.

The ends of the studs 10 have two slots 16 formed therein, which intersect each other at right angles. Each of the outer faces of the nuts 11 has holes 17 emerging therefrom, which holes 17 pass through the nuts 11 so as to vregister with the slots 16 of the studs 10 when the nuts 11 are se* cured upon the studs 10. A pin passes through two of the opposite holes 17 of the nut 11 and through one of the slots 16, see Figs. 3, 4.

In constructing pistons of great thickness, the preferred form shown in Figs. 1, 2, 3, 4, is used, as the length of stud 10 required if the modifications were used, would be too great. The pockets having the openings 13 are cored during the casting of the body 3, the openings 13 serving as a means for removing the cores. After the body 3, the rings 9 and the ring 8 have been machined, the studs 10 are screwed into the body 8, the ring S is slipped into place and the ring 9 is brought up against the ring S and against the plane surfaces ot the pist-on With which surfaces the ring eoaets. The nuts 11 are then screwed upon the ends of the studs 10 clamping the ring 9 tight against the body 8 on the plane surfaces of coaction of the tivo. The tivo members have their curved surfaces separated by a slight air space. After the nuts 11 have been brought up against the ring i), the pins 15 are dropped into the slots 12 which are in line with the holes 1T which register with slots 1G. The pins 15 are then passed through the holes 17 and slots 16 and bent over at the ends thus locking the nuts 11 into place. 1t it is desired to remove the nuts 11, the pins 15 are. bent back and are Withdrawn.

In the modified form, the construction is exactly the same except that the second ring 2t) is inserted, this ring 20 being clamped betvfeen the. ringand the piston 3. rlhis is done in order to perniit the use ot' as long` a stud lO as it is possible to use and still get the ring 8 in the desired position.

1t Will be seen that with the presentconstruction the long studs 10 give the structure a certain amount ot elasticity so as to compensate ior unequal expansion and contraction ot the clamped parts and still retain them in clamped position. The studs themselves cannot expand up to the amount of extension ot the studs under tension so that the parts never become loose. The use of the lock nuts 11 gives an etticient arrangement for securing the various members together under any desired degree ot tension.

Since the tull diameter oi' the body 3 the same as that of the ring E), it will be seen that it for any reason the larger face of the piston should be subjected 'to any extreme pressure, the studs 10 `will not be subjected to any resulting abnormal pressure because none of this pressure is borne by the ring 9, all of it being talren by the larger tace of the piston body It the treme pressure falls on the opposite tace oil the piston. the studs 1() will be subjected to a compressive strain to approximately the extent ot their cross section only. an important feature as such abnormal pressures may easily ruin a piston in which i This is the clamping studs are subjected to abnormal tension at such times. t

It should be understood that it is not desired to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled inl the art.

1t is claimed and desired to secure by Let-- ters Patent 1. 1n a piston, a plurality of coacting members, means including` a stud coacting with one of said members only, and a nut coaeting with another ot said members and with said stud, for holding said members in coaction, the elasticity ot said studs being' sutlieient to counteract shitting ot' the parts due to change in temperature.

2. ln a piston, the combination oi a piston body, a ring portion, and a stud coacting `with said body only. and a nut coaeting with said stud and said ring portion for cla-mping said ring portion to said body, said stud being of comparatively great length between the points of application of said stud to said body, and said nut to said stud.

3. 1n a piston, a plurality of coacting members, means including a plurality ot studs coacting with one oitl said members only, and a plurality of nuts enacting with said studs and with another oi said members, for holding said members in coaction, the elasticity of said studs being sutiicieut to counteract shitting of said members due to change in temperature.

el. ln a piston, a piston body, a ring, a stud iiXed to said body and passing Jfreely through said ring, and a nut on said stud for clamping said ring to said body, said stud being of con'iparatively great length between its point ot attachment to said body and the point ot application of said nut to said stud.

In a piston, a body member, a ring member, and means including a long stud tired to one of said members and passing freely through the other of said members, and a nut coacting with said stud and With said other member, for clamping the members together.

ln testimony whereof, l atlix my signature in the presence of tivo Witnesses.

EDVARD T. ADAMS.

lllituesses ll. C. CAsn, (it. F. DE lVnrN. 

